>I don't think the C<for> construct would be dealing with real >superpositions at the top level. I was just thinking about stealing >the | and & notation.
so, "|", "&", are special "meta-comma" operators that create a (meta:-) "list" with additional relation between entries. this (meta)list expands differently in for(...), when(...) , bits(...), any(...), all(...) . and probably in no special context it implies enclosing any(...) or all(...). so now we will have 4 "comma" operators : ";" | "," & "|" , "&" ; ? arcadi.
